Our objectives are to better define interactions between potentially oncogenic viruses and human leukocytes. The viruses to be studied include cytomegalovirus (CMV), herpes simplex virus (HSV), and type-c oncoviruses. We will attempt to clarify relationships between polymorphonuclear leukocytes (PMNL) or their bone marrow precursors and CMV, with respect to virus replication and PMNL function. This information will be used to develop means to eliminate latent virus from potentially infectious donor blood and prevent post-transfusion CMV mononucleosis will be explored, as will be the HLA types underlying this and other CMV syndromes. We will explore the mechanisms underlying HSV latency and productive infection in a chronically infected human T lymphoblastoid cell line, and will examine the effects of the virus on cell characteristics such as surface antigenicity and proliferation rate. We will determine if concepts that we have developed from studies of interactions between murine leukocytes and type-C oncoviruses are applicable to humans. Periheral blood leukocytes and leukocyte-derived cell lines will be infected with primate type C oncoviruses. The kinetics of such infections will be determined and alterations in lymphocyte function (transformation, autoreactivity, suppressor activity) will be evaluated. We will complete enrollment of patients into a double-blind placebo-controlled trial of human leukocyte interferon in renal transplant recipients and continue to monitor them for immunopathological and neoplastic consequences of infection.